As the federal government’s social distancing guidelines expire Thursday to be replaced by less stringent advice, health officials worry some governors may relax the measures prematurely and the public will become complacent — even as an estimated 20,000 new cases of the disease caused by the coronavirus are reported daily.

With covid-19 deaths still increasing by more than 1,000 each day, they say the danger is not over. And without the testing capacity to safely send people back to work, or enough workers to conduct large-scale contact tracing — meaning tracking all the people an infected individual has come into contact with — social distancing remains the most effective way to limit the spread of the virus.

Administration officials say the distancing measures have been replaced by White House guidance on how states should reopen — which include less stringent social distancing recommendations. But health experts say that does not offer individuals clear recommendations about how to navigate their daily lives and could unleash new outbreaks in states that push to reopen too early and too fast.

“You don’t want people to misconstrue the expiration of these guidelines as a recommendation that it’s okay to go back to your normal life, because it’s not,” said Richard Besser, former acting director of the Centers for Disease Control and Prevention, who said that neither the agency, nor the administration had offered a clear explanation on why states could begin to relax such measures.

He added that the CDC should clearly state that “as you start to reduce social distancing, there will be more cases of the disease.”

Georges Benjamin, executive director of the American Public Health Association, said the CDC was under pressure to defer to the states despite the disease’s rampant spread because of White House eagerness to get the economy up and running again.

“I’m not sure they’re being driven completely by the science here,” he said. “They’re trying to do the best they can given that they’re being driven to some extent by the White House.”

Vice President Pence, the head of the White House coronavirus task force, said on Wednesday that social distancing measures were part of the administration’s reopening guidance for states. Several senior administration officials echoed that, saying it is now up to state and local officials to decide how best to reopen, given the virus’ uneven spread throughout the country.

But some of those officials have also expressed concern that some states are moving ahead too quickly, including South Carolina and Georgia, where Gov. Brian Kemp allowed tattoo parlors, hair and nail salons and bowling alleys to reopen on April 24. Trump rebuked Kemp’s decision during a briefing last week.

That decision also reportedly blindsided the governor’s own health advisers, not to mention many local officials.

“Reopening the state and relaxing social-distancing measures now is irresponsible and could even be deadly,” wrote Atlanta Mayor Keisha Lance Bottoms in The Atlantic. “I strongly believe that our health-care system is not overwhelmed because we have been socially distancing. And while staying at home may be inconvenient for many people, there is nothing essential about going to a bowling alley during a pandemic.”

Back on March 16, the administration unveiled an initiative called “15 days to stop the spread” that urged people to work from home whenever possible, avoid social gatherings of more than 10 people, or eating or drinking at bars, restaurants and food courts. Trump extended the guidelines for another 30 days at the beginning of the month, through April 30.

The administration’s reopening guidance still urges states to incorporate social distancing, but relaxes the recommendations. The initial phase urges individuals to avoid socializing in groups of more than 10 people when people are unable to remain six feet apart, and says that individuals should maximize physical distance from others in public.

“The current guidelines, I think you can say, are very much incorporated in the guidance that we’re giving states to open up America again,” Pence said.

A senior administration official said that the CDC will keep the guidance on how to “stop the spread” in 30 days on its website, until it is replaced with finalized recommendations from the White House. That is expected to include expanded guidelines to allow the phased reopening of schools and camps, child-care programs, certain workplaces, houses of worship, restaurants and mass transit, representing the most detailed guidance to date.

“They have a bit of a muddled message about what people should be doing, and that you don’t know based on who’s talking what message you’re going to get,” said Joshua Sharfstein, professor at the Johns Hopkins Bloomberg School of Public Health. "A really important thing to understand when we don’t have a highly effective treatment or vaccine — communication is the medicine. Communication is getting people to take actions to protect themselves.

"If that message is muddled,” he said, it undermines the response.

The administration’s guidance that people wear face coverings in public will remain in place and there is no planned end date, a senior administration official said.

Some officials and experts said it made sense to defer to the states on when and how to reopen, but raised concern that allowing the social distance guidelines to expire without clear and detailed advice on how to reopen could cause confusion.

Marcus Plescia, chief medical officer for the Association of State and Territorial Health Officials, said the biggest concern from his members is that the CDC has only just started putting out detailed guidance on how various businesses can safely reopen.

“We’re making decisions on it right now,” he said. “It is a little concerning when we know through the media that there’s more materials out there than are necessarily being disseminated — we would like to have access to all of that.”